1. Field of the Invention
The present invention relates to a storage system and a remote copy recovery method, for example, is suitable for application to a 3DC (Data Center) system.
2. Description of the Related Art
Conventionally, as countermeasures against natural calamities (disasters recovery) in a storage system, a technique has been known that data written in a primary logical volume of a storage device operated by a certain site is copied to a secondary logical volume of a storage device installed in a site remote from the site for backup (hereinafter, referred to as “remote copy”).
In recent, a storage system has been proposed much, which is also called a 3DC system, that data written in a primary logical volume of a first storage device installed in a first site operated is transmitted to a third storage device installed in a third site via a second storage device installed in a second site, and, in the third storage device, the data is copied to a secondary logical volume provided by the third storage device.
For instance, in such 3DC system, a technique is disclosed in the Patent Document 1 that the data as a transmitting object is transmitted to the third storage device without an intermediate site (the second site) holding the data. According to such method, a logical volume with the same capacity as the primary logical volume of the second storage device is not necessary to prepare, and thus there is an advantage to build the 3DC system at a low cost.    [Patent Document 1] JP-A-2005-309550
However, in the 3DC system, when an obstacle occurs in a network for connecting between, for example, the second and the third storage devices, all of the data of remote copying object in the first storage device are transmitted to the third storage device via the second storage device after the corresponding network was recovered from the obstacle. With this, there is a problem in that it takes much time to return the operation of the 3DC system to a normal operation after the network was recovered from the obstacle.